package com.fanhao.dllo.justforyou.volley;

import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.toolbox.ImageLoader;
import com.android.volley.toolbox.StringRequest;
import com.android.volley.toolbox.Volley;
import com.fanhao.dllo.justforyou.application.BaseApplication;

import java.util.HashMap;
import java.util.Map;


/**
 * Created by yaolin on 15/10/22.
 */

//单例模式
public class VolleySingleton {

    //  private static VolleySingleton instance = new volleySingleTon();

    // 声明类本身的一个静态对象
    private static VolleySingleton instance;
    // 声明队列的对象
    private RequestQueue queue;
    private ImageLoader imageLoader;



    // 构造方法私有，防止外部类new此对象
    private VolleySingleton() {
        // 初始化队列
        queue = getQueue();
        imageLoader = new ImageLoader(queue, new DoubleCache());
    }

    //public static VolleySingleton getInstance(){
    //return instance;
    //}
    // 公布一个静态方法，用于获取本类的实例
    public static VolleySingleton getInstance(){
        if(instance == null) {
            // 同步代码块，防止多线程同时执行
            synchronized (VolleySingleton.class) {
                if (instance == null) {
                    instance = new VolleySingleton();
                }
            }

        }
        return instance;
    }
    // 获取RequestQueue实例的方法
    private RequestQueue getQueue() {
        if (queue == null) {
            // 防止Activity的Context一直被占用
            queue = Volley.newRequestQueue(BaseApplication.getContext());
        }
        return queue;
    }
    // 定义一个默认的Request的tag
    public static final String TAG = "VolleySingleton";
    public <T> void addRequest(Request<T> request){
        request.setTag("TAG");
        queue.add(request);
    }

    // 重载一个方法，给Request添加自定义的tag
    public <T> void addRequest(Request<T> request, Object tag) {
        request.setTag("TAG");
        queue.add(request);
    }

    public void addStringRequest(String url,Response.Listener listener,
                                 Response.ErrorListener error){
        StringRequest stringRequest = new StringRequest(url,listener,error){
            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                HashMap<String, String> map = new HashMap<String, String>();
                map.put("Accept-Encoding", "");
                return map;
            }
        };
        addRequest(stringRequest);

    }

    // 将Request从RequestQueue中移除，取消网络请求
    public void removeRequest(Object tag) {
        queue.cancelAll(tag);
    }

    public ImageLoader getImageLoader() {
        return imageLoader;
    }
}
